Source Sans Pro was designed by Paul D. Hunt as Adobe's first open
source typeface family, conceived primarily as a typeface for user
interfaces

The typeface is inspired by the forms of the American Type Founders'
gothics by Morris Fuller Benton. It is currently available in six
weights, from ExtraLight to Black, in upright and italic styles. The
typeface has wide language support for Latin script, including Western
and Eastern European languages, Vietnamese, pinyin Romanization of
Chinese, and Navajo. 
